diff --git a/yaml/converter/legacy/internal/testdata/matrix_1.yml b/yaml/converter/legacy/internal/testdata/matrix_1.yml
new file mode 100644
index 0000000..77e3331
--- /dev/null
+++ b/yaml/converter/legacy/internal/testdata/matrix_1.yml
@@ -0,0 +1,19 @@
+
+pipeline:
+  test:
+    image: golang:${GO_VERSION}
+    commands:
+    - go test -v ./...
+
+services:
+  redis:
+    image: redis:2.6
+
+matrix:
+  include:
+    - GO_VERSION: 1.11
+      REDIS_VERSION: 2.6
+    - GO_VERSION: 1.10
+      REDIS_VERSION: 2.6
+    - GO_VERSION: 1.9
+      REDIS_VERSION: 2.6
diff --git a/yaml/converter/legacy/internal/testdata/matrix_1.yml.golden b/yaml/converter/legacy/internal/testdata/matrix_1.yml.golden
new file mode 100644
index 0000000..a78c2a6
--- /dev/null
+++ b/yaml/converter/legacy/internal/testdata/matrix_1.yml.golden
@@ -0,0 +1,61 @@
+---
+kind: pipeline
+name: matrix-1
+
+platform:
+  os: linux
+  arch: amd64
+
+steps:
+- name: test
+  pull: default
+  image: golang:1.11
+  commands:
+  - go test -v ./...
+
+services:
+- name: redis
+  pull: default
+  image: redis:2.6
+
+---
+kind: pipeline
+name: matrix-2
+
+platform:
+  os: linux
+  arch: amd64
+
+steps:
+- name: test
+  pull: default
+  image: golang:1.10
+  commands:
+  - go test -v ./...
+
+services:
+- name: redis
+  pull: default
+  image: redis:2.6
+
+---
+kind: pipeline
+name: matrix-3
+
+platform:
+  os: linux
+  arch: amd64
+
+steps:
+- name: test
+  pull: default
+  image: golang:1.9
+  commands:
+  - go test -v ./...
+
+services:
+- name: redis
+  pull: default
+  image: redis:2.6
+
+...
diff --git a/yaml/converter/legacy/internal/testdata/matrix_2.yml b/yaml/converter/legacy/internal/testdata/matrix_2.yml
new file mode 100644
index 0000000..58ba6a5
--- /dev/null
+++ b/yaml/converter/legacy/internal/testdata/matrix_2.yml
@@ -0,0 +1,19 @@
+
+pipeline:
+  test:
+    image: golang:${GO_VERSION}
+    commands:
+    - go test -v ./...
+
+services:
+  redis:
+    image: redis:${REDIS_VERSION}
+
+matrix:
+  GO_VERSION:
+  - 1.11
+  - 1.10
+
+  REDIS_VERSION:
+  - 2.6
+  - 2.8
diff --git a/yaml/converter/legacy/internal/testdata/matrix_2.yml.golden b/yaml/converter/legacy/internal/testdata/matrix_2.yml.golden
new file mode 100644
index 0000000..609709d
--- /dev/null
+++ b/yaml/converter/legacy/internal/testdata/matrix_2.yml.golden
@@ -0,0 +1,81 @@
+---
+kind: pipeline
+name: matrix-1
+
+platform:
+  os: linux
+  arch: amd64
+
+steps:
+- name: test
+  pull: default
+  image: golang:1.11
+  commands:
+  - go test -v ./...
+
+services:
+- name: redis
+  pull: default
+  image: redis:2.6
+
+---
+kind: pipeline
+name: matrix-2
+
+platform:
+  os: linux
+  arch: amd64
+
+steps:
+- name: test
+  pull: default
+  image: golang:1.11
+  commands:
+  - go test -v ./...
+
+services:
+- name: redis
+  pull: default
+  image: redis:2.8
+
+---
+kind: pipeline
+name: matrix-3
+
+platform:
+  os: linux
+  arch: amd64
+
+steps:
+- name: test
+  pull: default
+  image: golang:1.10
+  commands:
+  - go test -v ./...
+
+services:
+- name: redis
+  pull: default
+  image: redis:2.6
+
+---
+kind: pipeline
+name: matrix-4
+
+platform:
+  os: linux
+  arch: amd64
+
+steps:
+- name: test
+  pull: default
+  image: golang:1.10
+  commands:
+  - go test -v ./...
+
+services:
+- name: redis
+  pull: default
+  image: redis:2.8
+
+...